package com.juc.lock;

import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
 * Lock三部曲
 * 1、 new ReentrantLock();
 * 2、 lock.lock();加锁
 * 3、 finally=> lock.unlock(); 解锁
 */
public class LockDemo2 {
    public static void main(String[] args) {
        // 并发：多线程操作同一个资源类, 把资源类丢入线程
        Ticket2 ticket = new Ticket2();
        // @FunctionalInterface 函数式接口，jdk1.8 lambda表达式 (参数)->{ 代码 }
        new Thread(() -> {
            for (int i = 1; i < 40; i++)
                ticket.sale();
        }, "A").start();
        new Thread(() -> {
            for (int i = 1; i < 40; i++)
                ticket.sale();
        }, "B").start();
        new Thread(() -> {
            for (int i = 1; i < 40; i++)
                ticket.sale();
        }, "C").start();
    }
}

class Ticket2 {
    // 属性、方法
    private int number = 30;
    Lock lock = new ReentrantLock();

    public void sale() {
        lock.lock(); // 加锁
        try {
            // 业务代码
            if (number > 0) {
                System.out.println(Thread.currentThread().getName() + "卖出了" +
                        (number--) + "票,剩余：" + number);
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            lock.unlock(); // 解锁
        }
    }
}
